Do Norepinephrine and Estradiol Affect the Growth of Escherichia coli and Expressions of Mar Genes?

Abstract

Objective: Human hormones have been shown to regulate antibiotic resistance levels, pathogenicity, and growth of bacteria. In our study, we aimed to detect the possible effects of norepinephrine (NE) and estradiol (Est) on growth and expression of chromosomal multiple antibiotic resistance (mar) locus and related genes (ompF, marA, tolC, acrA, marR and acrB) in Escherichia (E) coli SPC105. Material and Method: Serum supplemented SAPI (control) and serum SAPI containing norepinephrine (0.0017 µg/mL, 0.04 µg/ mL, and 100 µg/mL) and estradiol (0.4 ng/mL, 3 ng/mL, 300 ng/mL) was used to grow E. coli SPC105. Growth alterations were determined using the turbidimetric method while the gene expression levels were examined by quantitative polymerase chain reaction (qPCR). Results: It was shown that, NE and Est in all concentrations were shown to affect (reduce/enhance due to incubation periods or hormone concentrations) the growth of E. coli SPC105 apart from the high-level Est concentration. Expression levels of all six target genes were shown to be significantly enhanced in the presence of all concentrations of both NE and Est. Conclusion: Our results constitute new data on the possible influences of these hormones on the growth and expressions of mar operon on transcriptional levels in the E. coli SPC105 strain.